Google, meanwhile, is the master algorithm. Yes, there are lots of people at Google, too, including many sales and support staff. But Google's culture is dominated by engineers, the sort of high-GPA geniuses who can answer all of the brain-teaser Google interview questions, and by the image of being clean and non-evil.

Sure, it's possible that Google could promise Groupon complete autonomy, with the freedom to maintain and grow its counter-culture, and to hire its staff the way it always has, with Google's assistance mainly for infrastructure and investment. YouTube is sort of like this, even 4 years after being acquired.

DoubleClick, on the other hand, was swallowed whole, and quickly Google-fied. Same with pretty much every other Google acquisition, large and small. And that's the sort of thing that could totally screw up Groupon.